Topaz coated to cover poor polish?

Hi Orchid,

We put some blue topaz into an ultrasonic detergent soak overnight
and it came out cloudy looking, as if there were a film of soap on
the pavilion. Tried scrubbing with alcohol to no avail. Further
inspection showed that the pavilion facets were basically unpolished
with many little scratches visible. So it seems that some type of
coating was used instead of a proper polish. Possibly oil or ? We
still have quite a few of these so I think we will be inspecting
them in the daylight, and then we’ll decide what to do.

Has anyone else ever seen this type of thing before? I hope this is
not a common new thing.

D.

Dear D.

I have never heard of this happening before. Is the stone real blue
topaz or a stone coated with a color? They treat topaz and quartz
with what I understand is a plating of titanium, possibly a vapor
deposit. They can get any color imaginable. You might see these
stones marketed as “spice” topaz, etc. I would be very curious to
know what you find. This is a great concern to jewelers and stone
dealers alike.

Sincerely, Diane
Dikra Gem Inc.

Hi all,

Upon checking out the rest of the lot and other stones from the same
supplier we found that a few (3 or 4) had the same fine polishing
lines on the pavilion facets after cleaning.

We also found that the same detergent took the polish off some
charoite and chrysocolla cabs, don’t know if these were coated with
something as well (could be waxed?) or if it actually damaged the
stones. It does not appear to be a colored coating of the so called
"azotic" type, this is regular blue topaz, the cooked and irradiated
stuff that’s a couple bucks a carat wholesale. Since it was only a
few stones out of a good sized lot we are still selling it though we
are inspecting each stone for signs of this strange treatment closely
before setting.

That’s where it’s at for now, I guess we’ll be louping topaz before
buying it from now on.

Thanks for being Orchid,
Douglas